首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   953753篇
  免费   68693篇
  国内免费   1482篇
耳鼻咽喉   13269篇
儿科学   24853篇
妇产科学   23628篇
基础医学   136150篇
口腔科学   29020篇
临床医学   82270篇
内科学   188870篇
皮肤病学   19852篇
神经病学   73975篇
特种医学   37694篇
外国民族医学   79篇
外科学   155551篇
综合类   18223篇
现状与发展   1篇
一般理论   236篇
预防医学   62467篇
眼科学   21699篇
药学   74011篇
  3篇
中国医学   2194篇
肿瘤学   59883篇
  2018年   9512篇
  2017年   7424篇
  2016年   8188篇
  2015年   9372篇
  2014年   12660篇
  2013年   18245篇
  2012年   25268篇
  2011年   26322篇
  2010年   15508篇
  2009年   14899篇
  2008年   25699篇
  2007年   26880篇
  2006年   27675篇
  2005年   26657篇
  2004年   25753篇
  2003年   24697篇
  2002年   24284篇
  2001年   55226篇
  2000年   57071篇
  1999年   47457篇
  1998年   11019篇
  1997年   9673篇
  1996年   9831篇
  1995年   9135篇
  1994年   8463篇
  1993年   7764篇
  1992年   35834篇
  1991年   34249篇
  1990年   33023篇
  1989年   32190篇
  1988年   29310篇
  1987年   28551篇
  1986年   26586篇
  1985年   25399篇
  1984年   18024篇
  1983年   15299篇
  1982年   7893篇
  1981年   6872篇
  1979年   15932篇
  1978年   10717篇
  1977年   9171篇
  1976年   7936篇
  1975年   8729篇
  1974年   10571篇
  1973年   9956篇
  1972年   9453篇
  1971年   8952篇
  1970年   8532篇
  1969年   8045篇
  1968年   7291篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
A METHOD FOR CONTINUOUS SPINAL ANESTHESIA: A PRELIMINARY REPORT   总被引:1,自引:1,他引:0  
Lemmon WT 《Annals of surgery》1940,111(1):141-144
  相似文献   
992.
993.
994.
995.
996.
Acute encephalopathy associated with influenza and other viral infections   总被引:7,自引:0,他引:7  
Acute encephalopathy is the most serious complication of pediatric viral infections, such as influenza and exanthem subitum. It occurs worldwide, but is most prevalent in East Asia, and every year several hundreds of Japanese children are affected by influenza-associated encephalopathy. Mortality has recently declined, but is still high. Many survivors are left with motor and intellectual disabilities, and some with epilepsy. This article reviews various syndromes of acute encephalopathy by classifying them into three major categories. The first group caused by metabolic derangement consists of various inherited metabolic disorders and the classical Reye syndrome. Salicylate is a risk factor of the latter condition. The second group, characterized by a systemic cytokine storm and vasogenic brain edema, includes Reye-like syndrome, hemorrhagic shock and encephalopathy syndrome, and acute necrotizing encephalopathy. Non-steroidal anti-inflammatory drugs, such as diclofenac sodium and mephenamic acid, may aggravate these syndromes. Severe cases are complicated by multiple organ failure and disseminated intravascular coagulation. Mortality is high, although methylprednisolone pulse therapy may be beneficial in some cases. The third group, characterized by localized edema of the cerebral cortex, has recently been termed acute encephalopathy with febrile convulsive status epilepticus, and includes hemiconvulsion-hemiplegia syndrome and acute infantile encephalopathy predominantly affecting the frontal lobes. Theophylline is a risk factor of these syndromes. The pathogenesis is yet to be clarified, but an increasing body of evidence points to excitotoxicity and delayed neuronal death.  相似文献   
997.
An 11‐year‐old Gordon setter bitch was presented with a history of progressive weakness in the right hind limb associated with pain in the lumbar spine. Neurological deficits consisted of ataxia, monoparesis, muscle atrophy and spontaneous over‐knuckling of the affected limb. A large ‘juxtaarticular’ cyst located in a right dorsolateral position of the intervertebral foramen at L3–L4 was diagnosed by magnetic resonance imaging. The cyst was removed through a modified laminectomy. The dog recovered quickly and returned to the owners 4 days after surgery with slight neurological symptoms. During the follow‐up examination 2 and 6 months later, the Setter showed normal gait and neurological examination.  相似文献   
998.
Purpose Post operative monitoring is crucial for the success of microsurgical free tissue transfer. Sophisticated and expensive methods are available for monitoring. We propose a novel technique using digital photography and the internet as a reliable and cost effective method to monitor free tissue transfers. Methods 163 micro‐vascular procedures were monitored using this technique over 8 months. Serial photographs taken to show flap color. Capillary refill time, pin prick‐ bleed time and color and hand held Doppler signal was recorded in the movie mode of a standard 5 mega pixel camera with duration of 15 seconds. Data was sent to the surgeon at regular intervals and or as deemed necessary. Results Analysis of the 67 cases is presented. 5 re‐explorations were done. The early diagnosis of venous congestion was possible using this technique. Timely intervention contributed to the success of the re‐explorations and these flaps could be salvaged. The file size of images was in the range of 1 MB–6 MB. The file size of an entire set of images ranged about 7 MB–9 MB. These were sent across the ADSL internet lines. Conclusion The use of the digital images and the internet allow reconstructive surgeons to have a reliable picture of the state of their free tissue transfers. This permits decrease in observer error and saves valuable time which otherwise needs to be spent to verify situations of doubt and offers an ideal solution to the logistic problem of having to visit the patient in case of doubt.  相似文献   
999.
Primary squamous cell carcinoma is an extremely rare tumour of the thyroid gland. A case of an elderly lady who was diagnosed to have primary squamous cell carcinoma of the thyroid gland is presented and the role of radiotherapy is discussed.  相似文献   
1000.
Teeth with white spot lesions (WSL) might be more prone to enamel loss during bracket debonding. This in vitro study compared enamel loss from teeth with (n = 14) and without (n = 14) WSL after polishing with low-speed finishing burs or disks (Sof-Lex, 3M ESPE, St Paul, Minn). Debonded surfaces were analyzed with a contact stylus profilometer, and digitized data were compared with baseline readings by using AnSur NT software (Regents, University of Minnesota, Minneapolis, Minn). Specimen surfaces were also examined with a scanning electron microscope. Two-way analysis of variance was performed to analyze the data. In teeth without WSL, the volume losses were 0.16 mm(3) for the bur group and 0.10 mm(3) for the disk group; the mean maximum depths were 47.7 microm for the bur group and 54.3 microm for the disk group. In teeth with WSL, the volume losses were 0.06 and 0.17 mm(3), and the mean maximum depths were 35.1 and 48.7 microm for the bur and disk groups, respectively. There were no significant differences in enamel loss between the 2 groups of teeth without WSL (P =.12). However, in teeth with WSL, the burs removed less enamel than the disks (P = 0.006). Scanning electron microscope examination showed that any damage on the enamel surface was usually located in the cervical third of the teeth. On most specimens, even though tooth surfaces appeared resin-free to the naked eye, there were remnants of it. The differences between groups were so small that they might be clinically insignificant.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号